What exactly are you not understanding? Please explain.
The sizing chart has measurements for the classics (chest / length / shoulder).
If the chest measurement is the one throwing you off is because that's 1/2 of your chest circumference.
Let me know how i can help.

Hi Ray, I understand where you are coming from, however that is only on certain kinds of garment dye shirts like pigment dyes. I can guarantee this will not be the case with these items and the garment dye is only a process used to make the product softer with natural highs and lows in the coloring. There is no bleeding and the quality and garment will last you a long time with proper washing.